Almost nine out of 10 people who took part in a recent poll by the welfare rights charity Lasa think that the Conservatives' big society agenda will make it harder for charities to access the infrastructure support they need.
An online survey prompted 425 people who work for charities to give their opinions on how the big society agenda will affect the voluntary sector in future.
Early findings from the poll, which is due to be released in full on Wednesday, show that 88 per cent of respondents thought there would be less funding for infrastructure charities, and 82 per cent said it would be harder for front-line charities to access support from them.
Terry Stokes, chief executive of Lasa, said less funding for and support from such charities would be "very, very damaging" for the sector.
"People need to be effectively resourced to deliver front-line services - things simply don't run on thin air," he said.
"At a time of much uncertainty, when the need for advice is increasing, there are, at the same time, fewer resources being deployed to support it."
Stokes said charities should address the problem by helping each other to make the case for second and third-tier charities.
The research also found that 60 per cent of respondents thought the big society would mean more collaboration in the sector.
"Collaboration among charities at the moment is a good thing," said Stokes.
"We need to show we're actively collaborating with those with similar services.
"We must show we are being judicious in how we spend our money and look for efficiencies where we can make them."